<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>padding</title>
    <style>
        div {
            box-sizing: border-box;
            height: 300px;
            width: 300px;
            /* 元素高度为0，padding 也可以挤出来高度，也就是boxSizing并不能限制padding */
            /* padding: 10px 0px; */


            border: 10px solid black;
            background-color: rebeccapurple;
        }

    </style>
</head>
<body>
    <div>
        
    </div>
</body>
</html>